Abstract.Moringa peregrina which is one of the most valuable and economically important medicinal species in the Egyptian desert has become one of the most endangered trees due to unmanaged grazing and over-collection. The present study aims to provide ecological assessment of the species and to investigate whether progeny from the remnant fragmented populations show reduced fitness. Sixteen sites containing a total of 197 trees were sampled upon survey of Wadis in South Sinai, where vegetation parameters and associated species were recorded. Variation in edaphic factors, phenotypic traits, germination, and early life-history fitness were assessed and analyzed. The results indicated that M. peregrina has narrow distribution and grows on cliffs and at the base of hills (300 -800 m a.s.l.) with very rugged topography. Almost all the reproductive trees grow on south facing slopes and crevices of metamorphic rocks. The study clearly showed that the studied populations have very low early stage fitness estimated as an index of maternally affected life-history characters. The study suggested that the deteriorated environmental circumstances have affected negatively the fitness of maternal plants in small populations and the performance of their offspring. It concluded that direct protection is urgently needed to stop further deterioration of the populations and to improve their number and size.

Acacia trees in Sinai desert are suffering population decline. This study aims to explore this assumption and to determine the effects of grazing and urbanization on size structure of Acacia tortilis subsp. raddiana along a gradient of water availability in Wadi Feiran basin, South Sinai, Egypt. Size structure of 289 Acacia trees in thirteen isolated populations was analysed. Catchment area and lineament density as water availability indicators were calculated. Effects of grazing and urbanization on Acacia populations were evaluated. A strong positive correlation was recognized between tree height, crown diameter and trunk circumference. Acacia tree density and crown diameter are positively correlated with water availability indicators. Population structure of A. tortilis is characterized by absence of juveniles, clear reduction in numbers of small and large categories and increasing in medium categories. This pattern indicates very low recruitment and high mortality of small and large trees. The variation in water availability may have considerable effects on the structure of A. tortilis. Overgrazing, cutting and urbanization are the main causes of population decline of Acacia in Sinai desert. In addition, drought conditions and bruchid seed beetles aggravate the anthropogenic effect on recruitment of Acacia in South Sinai.

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Knowledge about plant diversity along disturbance gradients is essential for conservation and management of fragmented coastal habitats. This study examined the effects of human disturbance intensity in coastal habitats of Kuwait on diversity, composition, identity and assemblage of vascular plant species. Plant survey data from 113 plots (5 m×5 m each) were randomly selected in 51 sites at coastal fragmented habitats at three levels of disturbance intensities (high, moderate and low) and were statistically analyzed. The results revealed that about 76% of the recorded species are considered threatened species in Kuwait, most of which are being lost in high disturbed habitats. Disturbance led to the dominance of Zygophyllum qatarense, Cornulaca aucheri and Salsola imbricata, which are species of disturbance indicators. Richness, total plant cover and species diversity were higher in moderate and low disturbed habitats than in high disturbed habitats. Beta diversity between high and low disturbed habitats was higher than either between high and moderate, or between moderate and low disturbed habitats. Cluster analyses showed statistically significant differences in composition of plant assemblages, which indicate high beta diversity between the habitat types. Intensive urbanization and industrialization are among the most serious threats that contribute to declines in biological diversity and rapid fragmentation of coastal habitats in Kuwait. Establishing protective enclosures in the disturbed habitats, planting endangered and vulnerable species, and establishing a natural reserve at Nuwaiseeb are recommended conservation actions to avoid loss of the fragmented coastal habitats and to facilitate restoration of native plants.

Although the coastal salt marshes of Arabian Gulf have been altered extensively by human development activities, there is a paucity of data describing changes in the distribution and abundance of native coastal plant communities. The main objectives of this study are to determine vegetation condition, size structure, and conservation status of Nitraria retusa, a medicinal and salttolerant shrub, in disturbed and non-disturbed coastal salt marshes of Kuwait. Size measurements of Nitraria shrubs and nabkas, which are mounds of sediment developed around shrubs, were carried out in 50 quadrats (20 9 20 m 2 ), randomly selected inside and outside Sabah Al-Ahmad Natural Reserve. Species richness and soil properties of nabkas and interspaces, the open areas between the nabkas, were also measured. The results revealed that nabkas of Nitraria in non-disturbed sites are more stable and rich in plant diversity than those in disturbed sites. Mean height and mean canopy diameter of Nitraria shrubs, total plant cover, and species richness are significantly higher in non-disturbed sites than disturbed sites, which indicate the positive influences of conservation for long term on vegetation structure and species richness. The results of soil analyses indicate the important role of nabkas in providing refuges for plant life and species diversity. The present study indicates that more than 50 % of the N. retusa community has been lost during the last few decades. Therefore, N. retusa should be considered an endangered species in Kuwait. The reduction in vegetation cover, a decline in species richness, and the overall degradation of salt marshes are attributed to human development activities along the coast of Kuwait. Effective conservation actions for threatened species in degraded coastal salt marshes of this region include establishment of protective enclosures, prohibitions on development that adversely affects native plant communities, and the planting native salt-tolerant shrubs to facilitate regeneration.

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